Motor vehicle crashes are a leading cause of injury and death among adolescents. The Naturalistic Teenage Driving Study (NTDS), using objective measures ofrisky driving, found that novice teenage drivers have nearly four times the crash/near crash (CNC) rates and nearly five times higher rates of kinematic risky driving (KRD) (e.g., elevated gravitational force event rates) compared with adults (parents driving the same vehicles) (Simons Morton et al., 2015). Previous funding supported the development of a large data base, The Uniform Naturalistic Driving Study (UNTDS), made up of several naturalistic driving studies, including the NICHD-funded Naturalistic Teenage Driving Study (NTDS) with 42 teenage and 54 adult participants and the Supervised Practice Driving Study (SPDS) with 90 teenage and 114 adult participants, and the Transportation Research Board-funded SHRP2 (Strategic Highway Research Program) study with 281 novice 16-17 years old, a sample of 200 young drivers 18- 20 years old, a sample of 200 young adult drivers 21-25 years old, and a sample of 200 adult drivers 35-55 years old. The UNTDS data base is currently being composed and will provide a large sample of teenage and adult drivers that will allow analyses to confirm and extend the findings from NTDS. This new research would enable analyses of this data set for emerging questions of interest regarding the higher crash risk of novice drivers relative to experienced drivers related to the following: To what extent do novice drivers, relative to experienced drivers, moderate their driving behaviors under variable driving conditions? SUPPORTS Z1AHD001707